1. Field of the Invention
The present invention pertains to maintaining the safety of riders in highway vehicles. More particularly, the present invention pertains to the initiation of the inflation of passenger vehicle safety airbags that are intended to protect a rider from impact with the interior of the occupant enclosure of a vehicle.
2. Background
Inflatable safety restraint devices, or airbags, are mandated in most new highway vehicles. Airbags are typically included at least in the steering wheel and in the dashboard on the passenger side of a highway vehicle. In addition, such airbags are occasionally installed to inflate beside a vehicle occupant and provide side impact protection, to inflate in front of the legs and protect the knees from forward impact, or to inflate at other strategic locations within the occupant enclosure of a highway vehicle.
In the event of an accident, a collision sensor within the vehicle detects an impact situation and stimulates an inflator to produce pressurized gas. That pressurized gas is directed into an associated airbag, filling the cushion of the airbag, which then prevents any vehicle rider from impacting directly the interior surfaces of the occupant enclosure. The generation of compressed gas by the inflator is commenced through the electrical detonation of a small pyrotechnic initiator within the inflator. Inflatable airbags with associated inflators and initiators are usually manufactured together as passenger vehicle safety airbag modules, which are installed unit-wise at appropriate locations in vehicles.
A passenger-side, frontal-impact passenger vehicle safety airbag module is commonly installed behind the instrument panel of a vehicle at an airbag deployment window formed therethrough. A frontal-impact passenger vehicle safety airbag module is also commonly installed in the steering column for a vehicle to protect the driver. For both types of passenger vehicle safety airbag modules, the initiator in the inflator of the module is placed in electrical communication with the collision sensor of the vehicle, which may, for example, take the form of an accelerometer carried at a convenient location in the vehicle.